3D layers overview and resources

When you make a layer a 3D layer, the layer itself remains flat, but it gains additional properties: Position (z), Anchor Point (z), Scale (z), Orientation, X Rotation, Y Rotation, Z Rotation, and Material Options properties. Material Options properties specify how the layer interacts with light and shadows. Only 3D layers interact with shadows, lights, and cameras.

2D layers (left) and layers with 3D properties (right)

Individual characters within text layers can optionally be 3D sublayers, each with their own 3D properties. A text layer with Enable Per-character 3D selected behaves just like a precomposition that consists of a 3D layer for each character. All camera and light layers have 3D properties.

By default, layers are at a depth (z-axis position) of 0. In After Effects, the origin of the coordinate system is at the upper-left corner; x (width) increases from left to right, y (height) increases from top to bottom, and z (depth) increases from near to far. Some video and 3D applications use a coordinate system that is rotated 180 degrees around the x axis; in these systems, y increases from bottom to top, and z increases from far to near.

You can transform a 3D layer relative to the coordinate space of the composition, the coordinate space of the layer, or a custom space by selecting an axis mode.

You can add effects and masks to 3D layers, composite 3D layers with 2D layers, and create and animate camera and light layers to view or illuminate 3D layers from any angle. When rendering for final output, 3D layers are rendered from the perspective of the active camera. (See Create a camera layer and change camera settings.)

All effects are 2D, including effects that simulate 3D distortions. For example, viewing a layer with the Bulge effect from the side does not show a protrusion.

As with all masks, mask coordinates on a 3D layer are in the 2D coordinate space of the layer.

Convert 3D layers

When you convert a layer to 3D, a depth (z)
value is added to its Position, Anchor Point, and Scale properties,
and the layer gains Orientation, Y Rotation, X Rotation, and Material
Options properties. The single Rotation property is renamed Z Rotation.

When
you convert a 3D layer back to 2D, the Y Rotation, X Rotation, Orientation, and
Material Options properties are removed, including all values, keyframes, and
expressions. (These values cannot be restored by converting the
layer back to a 3D layer.) The Anchor Point, Position, and Scale
properties remain, along with their keyframes and expressions, but
their z values are hidden and ignored.

Convert a layer to a 3D layer

Select the 3D Layer switch for
the layer in the Timeline panel, or select the layer and choose
Layer > 3D Layer.

Convert a text layer to a 3D layer
with per-character 3D properties enabled

Convert a 3D layer to a 2D layer

Deselect the 3D Layer switch for the
layer in the Timeline panel, or select the layer and choose Layer >
3D Layer.

Show or hide 3D axes and layer
controls

3D axes are color-coded arrows: red for x,
green for y, and blue for z.

To show or hide 3D axes, camera and light wireframe icons, layer handles, and the point of interest, choose View > Show Layer Controls.

註解：

If the axis that you want to manipulate is difficult to see, try a different setting in the Select View Layout menu at the bottom of the Composition panel.

To show or hide a set of persistent 3D reference axes, click the Grid And Guides Options button at the bottom of the Composition panel, and choose 3D Reference Axes.

Chris and Trish Meyer provide a video tutorial on the ProVideo Coalition website that demonstrates the use of the 3D axis layer controls.

Move a 3D layer

Select the 3D layer that you want to
move.

Do one of the following:

In the Composition panel, use the Selection
tool to
drag the arrowhead of the 3D axis layer control corresponding to
the axis along which you want to move the layer. Shift-drag to move
the layer more quickly.

In the Timeline panel, modify the Position property values.

註解：

Press P to show Position.

To move selected layers so that their anchor points
are at the center in the current view, choose Layer > Transform
> Center In View or press Ctrl+Home (Windows) or Command+Home
(Mac OS).

Rotate or orient a 3D layer

You can turn a 3D layer by changing its Orientation
or Rotation values. In both cases, the layer turns around its anchor
point. The Orientation and Rotation properties differ in how the
layer moves when you animate them.

When you animate the Orientation
property of a 3D layer, the layer turns as directly as possible
to reach the specified orientation. When you animate any of the
X, Y, or Z Rotation properties, the layer rotates along each individual
axis according to the individual property values. In other words,
Orientation values specify an angular destination, whereas Rotation
values specify an angular route. Animate Rotation properties to
make a layer turn multiple times.

Animating the Orientation
property is often better for natural, smooth motion, whereas animating
the Rotation properties provides more precise control.

Rotate or orient a 3D layer in
the Composition panel

Select the 3D layer that you want to
turn.

Select the Rotation tool , and
choose Orientation or Rotation from the Set menu to determine whether
the tool affects Orientation or Rotation properties.

In the Composition panel, do one of the following:

Drag the arrowhead of the 3D axis layer
control corresponding to the axis around which you want to turn
the layer.

Drag a layer handle. Dragging a corner handle turns
the layer around the z axis; dragging a left or right center handle
turns the layer around the y axis; dragging a top or bottom handle
turns the layer around the x axis.

Drag the layer.

註解：

Shift-drag to constrain your manipulations
to 45-degree increments.

Rotate or orient a 3D layer in
the Timeline panel

Select the 3D layer that you want to
turn.

In the Timeline panel, modify the Rotation or Orientation
property values.

註解：

Press R to show Rotation and Orientation
properties.

Online resources about rotating
and orienting 3D layers

Donat Van Bellinghen provides some expressions on the AE Enhancers forum for placing and orienting a 3D layer in the plane defined by three points.

Axis modes

Axis modes specify on which set of axes a 3D layer is transformed. Choose a mode in the Tools panel.

Local Axis mode

Aligns the axes to the surface of a 3D layer.

World Axis mode

Aligns the axes to the absolute coordinates of the composition. Regardless of the rotations you perform on a layer, the axes always represent 3D space relative to the 3D world.

View Axis mode

Aligns the axes to the view you have selected. For example, suppose that a layer has been rotated and the view changed to a custom view; any subsequent transformation made to that layer while in View Axis mode happens along the axes corresponding to the direction from which you are looking at the layer.

Differences between the axis modes are only relevant when you have a 3D camera in a composition.

The Tools panel remembers the last-used 3D axis mode when you quit and restart After Effects.

註解：

The Camera tools always adjust along
the local axes of the view, so the action of the Camera tools is
not affected by the axis modes.

3D layer interactions, render order,
and collapsed transformations

The positions of certain kinds of layers in the layer
stacking order in the Timeline panel prevent groups of 3D layers
from being processed together to determine intersections and shadows.

A shadow cast by a 3D layer does not affect a 2D layer or any
layer that is on the other side of the 2D layer in the layer stacking
order. Similarly, a 3D layer does not intersect with a 2D layer
or any layer that is on the other side of the 2D layer in the layer
stacking order. No such restriction exists for lights.

Just like 2D layers, other types of layers also prevent 3D layers
on either side from intersecting or casting shadows on one another:

An adjustment layer

A 3D layer with a layer style applied

A 3D precomposition layer to which an effect, closed mask
(with mask mode other than None), or track matte has been applied

A 3D precomposition layer without collapsed transformations

A precomposition with collapsed transformations (Collapse Transformations switch
selected)
does not interfere with the interaction of 3D layers on either side—as
long as all of the layers in the precomposition are themselves 3D
layers. Collapsing transformations exposes the 3D properties of
the layers that compose the precomposition. Essentially, collapsing
transformations in this case allows each 3D layer to be composited
into the main composition individually, rather than creating a single
2D composite for the precomposition layer and compositing that into
the main composition. The tradeoff is that this setting removes your
ability to specify certain layer settings for the precomposition
as a whole—such as blending mode, quality, and motion blur.

Shadows cast by continuously rasterized 3D layers (including
text layers) are not affected by effects applied to that layer.
If you want the shadow to show the results of the effect, then precompose
the layer with the effect.

註解：

To ensure that the shadow remains where expected
on a 3D layer with a track matte, precompose the 3D layer and the
track matte layer together (but don’t collapse transformations),
and then apply the shadow to the precomposition.

Effects on continuously rasterized vector layers with 3D properties are rendered in 2D and then projected onto the 3D layer. This projection does not occur for compositions with collapsed transformations.